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Development and study on automatic balancer based on counter weight by magnetic force
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作者 Liu Heng Fan Hongwei +2 位作者 Jing Minqing Wang Renchao Zhi Jingjuan 《Engineering Sciences》 EI 2013年第1期35-38,共4页
Rotating machines are very sensitive to mass unbalance which has a harmful effect on its running accuracy and service life. Therefore,a variety of dynamic balancing methods and devices are studied to reduce the vibrat... Rotating machines are very sensitive to mass unbalance which has a harmful effect on its running accuracy and service life. Therefore,a variety of dynamic balancing methods and devices are studied to reduce the vibration caused by mass unbalance. On-line active balancing is a new balancing procedure which is more convenient and precise than the previous methods. In this paper,an electromagnetic balancer based on ring coils and permanent magnets is presented. The balancer has a simple structure and the self-locking function without clutch,and transfers power by the non-contact electromagnetic field. In order to justify the rationality of its design,a two-dimension(2D) electromagnetic finite element model is conducted to verify that this magnetic circuit has no flux leakage and saturation. A three-dimension (3D) 1/10 model of the balancer is built to obtain the self-locking torque and driving torque. Based on the research work above,an electromagnetic balancer is developed. By testing the balancer using COCO80,it is verified effective to reduce the rotor unbalance at the speed of 1300 r/min. 展开更多
关键词 electromagnetic balancer magnetic circuit SELF-LOCKING driving
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P-ACOHONEYBEE: A Novel Load Balancer for Cloud Computing Using Mathematical Approach 被引量:2
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作者 Sunday Adeola Ajagbe Mayowa O.Oyediran +2 位作者 Anand Nayyar Jinmisayo A.Awokola Jehad F.Al-Amri 《Computers, Materials & Continua》 SCIE EI 2022年第10期1943-1959,共17页
Cloud computing is a collection of disparate resources or services,a web of massive infrastructures,which is aimed at achieving maximum utilization with higher availability at a minimized cost.One of the most attracti... Cloud computing is a collection of disparate resources or services,a web of massive infrastructures,which is aimed at achieving maximum utilization with higher availability at a minimized cost.One of the most attractive applications for cloud computing is the concept of distributed information processing.Security,privacy,energy saving,reliability and load balancing are the major challenges facing cloud computing and most information technology innovations.Load balancing is the process of redistributing workload among all nodes in a network;to improve resource utilization and job response time,while avoiding overloading some nodes when other nodes are underloaded or idle is a major challenge.Thus,this research aims to design a novel load balancing systems in a cloud computing environment.The research is based on the modification of the existing approaches,namely;particle swarm optimization(PSO),honeybee,and ant colony optimization(ACO)with mathematical expression to form a novel approach called PACOHONEYBEE.The experiments were conducted on response time and throughput.The results of the response time of honeybee,PSO,SASOS,round-robin,PSO-ACO,and P-ACOHONEYBEE are:2791,2780,2784,2767,2727,and 2599(ms)respectively.The outcome of throughput of honeybee,PSO,SASOS,round-robin,PSO-ACO,and P-ACOHONEYBEE are:7451,7425,7398,7357,7387 and 7482(bps)respectively.It is observed that P-ACOHONEYBEE approach produces the lowest response time,high throughput and overall improved performance for the 10 nodes.The research has helped in managing the imbalance drawback by maximizing throughput,and reducing response time with scalability and reliability. 展开更多
关键词 ACO cloud computing load balancing swarm intelligence PSO P-ACOHONEYBE honeybee swarm
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Conception and Design of Active Balancer for Planar Mechanisms
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作者 ZHANG Ying YAO Yan-An CHA Jianzhong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第6期822-832,共11页
The dynamic balancing is an important issue in mechanism design.For the existing balancing methods,both passive and active ones,there is still room for improvement in adaplability and independency.In view of this,a co... The dynamic balancing is an important issue in mechanism design.For the existing balancing methods,both passive and active ones,there is still room for improvement in adaplability and independency.In view of this,a concept of active balancer is developed as a new solution for the dynamic balancing with more flexibility.The proposed balancer is an independent additional device with a control system inside,which consists of a two-degree-of-freedom(DOF)linkage and a controllable motor,and can be attached to a machine expediently with little change to its original structure and motion.One of the two inputs of the two-DOF linkage shares the same shaft with its output,which is connected to the input shaft of a machine to be balanced and driven by the original actuator.The other input is driven by the control motor.By properly selecting the speed trajectories of the control motor and link parameters of the two-DOF linkage,one or more dynamic effects of the mechanisms can be minimized or eliminated adaptively.The design procedure of the active balancer is put forward and a two-step optimization is developed to find out optimal design parameters of the balancer for various design requirements and constraints.Taking a force-balanced crank-rocker mechanism as the reference mechanism,numerical examples are given to illustrate the design procedure.The balancing effects of the proposed balancer are compared with those of the existing adding dyads(DYAD)method.The results show that the introduction of the control system provides the active balancer with better balancing effect and more flexibility than the DYAD method.A considerable reduction in the dynamic effects(input torque,shaking moment and shaking force)can be achieved for different balancing object by designing the structural and control parameters of the balancer,and the deterioration of dynamic performance caused by alterative working conditions can be compensated effectively by redesigning the control parameters. 展开更多
关键词 active balancing shaking moment input torque shaking force optimum balancing two-degree-of-freedom linkage
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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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A positive Buck-Boost voltage balancer for DC distribution system
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作者 ZHENG Huan JIANG DaoZhuo +3 位作者 ZHANG Chi YE LiXin XU Feng LIANG YiQiao 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第3期578-588,共11页
This paper analyzes the load unbalance problem and voltage fluctuation problem in a 3-wire DC distribution system.It also analyzes a solution to these problems;a positive Buck-Boost voltage balancer is proposed and ex... This paper analyzes the load unbalance problem and voltage fluctuation problem in a 3-wire DC distribution system.It also analyzes a solution to these problems;a positive Buck-Boost voltage balancer is proposed and explored in order to fulfill the requirements of high quality power supply for the loads on its load side.Compared with the conventional balancer,a positive Buck-Boost converter is added to solve the voltage fluctuation problem,and the theories and methods of the voltage balancer are extended to analyze the working principle,derive the design equations,explore the stability,and calculate the efficiency.Both simulations and small power experiments are carried out to verify the validity of the working principle,the topology,and the control strategy. 展开更多
关键词 DC distribution positive Buck-Boost converter voltage balancer load unbalance voltage fluctuation
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缺血性脑卒中突袭,这些护理要点能救命
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作者 王丽慧 宋秀云 《医食参考》 2026年第2期66-66,共1页
脑卒中,这一因脑部供血异常致使脑细胞死亡的疾病,正严重威胁着人们的健康。相关数据触目惊心,我国每年新发脑卒中患者约200万,其中缺血性脑卒中占比高达70%~80%。当身边有人突发缺血性脑卒中,掌握正确的急救护理要点,或许能在关键时刻... 脑卒中,这一因脑部供血异常致使脑细胞死亡的疾病,正严重威胁着人们的健康。相关数据触目惊心,我国每年新发脑卒中患者约200万,其中缺血性脑卒中占比高达70%~80%。当身边有人突发缺血性脑卒中,掌握正确的急救护理要点,或许能在关键时刻拯救生命。快速识别是开启急救的第一步快速识别缺血性脑卒中是急救的首要步骤,大家可以记住“BEFAST”口诀。B(Balance):留意患者是否平衡失调,比如突然行走困难、站立不稳;E(Eyes):观察患者眼睛,是否出现视力模糊、视野缺损;F(Face):让患者微笑,查看面部是否对称,如果出现一侧嘴角下垂的情况要引起警惕;A(Arms):让患者平举双臂,如果有一侧手臂无力下垂。很可能是大脑供血不足影响了肢体运动功能;S(Speech):患者说话是否言语不清、表达困难。 展开更多
关键词 健康 EYES BALANCE 缺血性脑卒中 急救护理
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AeroLOBE:A Deep Learning-based Novel Load Balancer for Aerial Communication to Enhance the Performance of 6G Networks
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作者 Tushar Vrind Debabrata Das 《Journal of Communications and Information Networks》 CSCD 2024年第4期390-400,共11页
While the low-altitude platform(LAP)-based aerial cells help improve the coverage and capacity for the telecom operator,the deployment and management of the aerial fleet is a non-trivial problem from both a capital ex... While the low-altitude platform(LAP)-based aerial cells help improve the coverage and capacity for the telecom operator,the deployment and management of the aerial fleet is a non-trivial problem from both a capital expenditure(CAPEX)and an operational expenditure(OPEX)perspective.On the one hand,it is critical to keep the fleet size to a minimum to reduce CAPEX,while on the other hand,it is critical to optimally associate user equipment(UE)with aerial cells in order to maximize the use of aerial cell resources and serve more pieces of UE.Existing research on balancing UE load among aerial cells discusses mechanisms like coverage and capacity optimization.To the best of our knowledge,this is the first time we have treated the forecasted data traffic volume for each user as well as inter-UE traffic consideration to jointly optimize capacity maximization for aerial cells,latency minimization in inter-UE communication,and aerial fleet size minimization.To this end,we present a deep learning-based novel aerial load balancer(AeroLOBE)for aerial communication using a novel constraint fractional group multiple knapsack problem(F-GMKP)formulation and the knapsack optimization(KO)for associating users to LAPs,thereby enhancing performance for the network.Through mathematical modelling and extensive simulation,we show that AeroLOBE reduces the latency of inter-UE communication by over 39% and improves the resource utilization by over 10%,while keeping the blocking rate and fleet reduction targets similar or marginally better than the available load balancing schemes in the literature. 展开更多
关键词 aerial communication load balancing user association
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Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review 被引量:1
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作者 Stiven Roytman Rebecca Paalanen +4 位作者 Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico I.Bohnen 《Neural Regeneration Research》 SCIE CAS 2025年第1期82-92,共11页
Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have ... Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging population.Posture and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous mechanisms.To effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory signals.The mechanisms which underpin the integration of these multisensory signals are the principal topic of the present work.Existing multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older adults.Insufficient emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and balance.In the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s disease.We also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older adults.Lastly,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases. 展开更多
关键词 aging BALANCE encephalography functional magnetic resonance imaging GAIT multisensory integration Parkinson’s disease positron emission tomography SOMATOSENSORY VESTIBULAR visual
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Machine learning approaches for predicting impact sensitivity and detonation performances of energetic materials 被引量:2
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作者 Wei-Hong Liu Qi-Jun Liu +1 位作者 Fu-Sheng Liu Zheng-Tang Liu 《Journal of Energy Chemistry》 2025年第3期161-171,共11页
Excellent detonation performances and low sensitivity are prerequisites for the deployment of energetic materials.Exploring the underlying factors that affect impact sensitivity and detonation performances as well as ... Excellent detonation performances and low sensitivity are prerequisites for the deployment of energetic materials.Exploring the underlying factors that affect impact sensitivity and detonation performances as well as exploring how to obtain materials with desired properties remains a long-term challenge.Machine learning with its ability to solve complex tasks and perform robust data processing can reveal the relationship between performance and descriptive indicators,potentially accelerating the development process of energetic materials.In this background,impact sensitivity,detonation performances,and 28 physicochemical parameters for 222 energetic materials from density functional theory calculations and published literature were sorted out.Four machine learning algorithms were employed to predict various properties of energetic materials,including impact sensitivity,detonation velocity,detonation pressure,and Gurney energy.Analysis of Pearson coefficients and feature importance showed that the heat of explosion,oxygen balance,decomposition products,and HOMO energy levels have a strong correlation with the impact sensitivity of energetic materials.Oxygen balance,decomposition products,and density have a strong correlation with detonation performances.Utilizing impact sensitivity of 2,3,4-trinitrotoluene and the detonation performances of 2,4,6-trinitrobenzene-1,3,5-triamine as the benchmark,the analysis of feature importance rankings and statistical data revealed the optimal range of key features balancing impact sensitivity and detonation performances:oxygen balance values should be between-40%and-30%,density should range from 1.66 to 1.72 g/cm^(3),HOMO energy levels should be between-6.34 and-6.31 eV,and lipophilicity should be between-1.0 and 0.1,4.49 and 5.59.These findings not only offer important insights into the impact sensitivity and detonation performances of energetic materials,but also provide a theoretical guidance paradigm for the design and development of new energetic materials with optimal detonation performances and reduced sensitivity. 展开更多
关键词 Energetic materials Machine learning Impact sensitivity Detonation performances Feature descriptors Balancing strategy
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Touristic urbanization and greening of coastal dune fields:A long-term assessment of a temperate sandy barrier of Argentina 被引量:1
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作者 GARZO Pedro Andrés DADON JoséRoberto ISLA Federico Ignacio 《Journal of Geographical Sciences》 2025年第1期206-230,共25页
Dune barrier systems represent highly sought-after coastal landscapes for tourism and urban development around the world.However,a century ago,they were considered hazardous environments due to their great dynamic nat... Dune barrier systems represent highly sought-after coastal landscapes for tourism and urban development around the world.However,a century ago,they were considered hazardous environments due to their great dynamic nature.As a result,stabilization practices were considered necessary.The systematic introduction of fast-growing exotic trees helped stabilize the sand,making it easier for tourism urbanization to take place,but also leading to erosion processes.This paper aims to assess long-term changes in vegetation cover over a large temperate barrier in Argentina.This complex region includes urban resorts,afforestation zones,and protected areas.A GIS-based geospatial analysis was conducted using a large satellite database(>350 images),and the future evolution of the vegetation was modeled.The results revealed two primary spatiotemporal patterns associated with a gradual expansion of vegetation cover,accompanied by a concurrent reduction in sandy areas.In 1986,the dune area comprised 75%more surface than vegetation,whereas in 2021,it represented 60%less than vegetation.Furthermore,the 2050 scenario suggests a potential 40%reduction of dunes in certain areas.It is necessary to enhance management actions aimed at maintaining dune mobility and ensuring local and regional sediment balance.Long-term management strategies must focus on restoring native plant communities and controlling invasive species,and avoiding new dune fixation initiatives based on the introduction of exotic species. 展开更多
关键词 nature reserves AFFORESTATION sediment balance dune management NDVI
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Long-term combined application of organic and inorganic fertilizers increases crop yield sustainability by improving soil fertility in maize-wheat cropping systems 被引量:1
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作者 Jinfeng Wang Xueyun Yang +3 位作者 Shaomin Huang Lei Wu Zejiang Cai Minggang Xu 《Journal of Integrative Agriculture》 2025年第1期290-305,共16页
Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in t... Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in the long term under the combined application of organic and inorganic fertilizers. Three long-term field trials were conducted to investigate the effects of organic amendments on the grain sustainable yield index(SYI), soil fertility index(SFI)and nutrient balance in maize–wheat cropping systems of central and southern China during 1991–2019. Five treatments were included in the trials: 1) no fertilization(control);2) balanced mineral fertilization(NPK);3) NPK plus manure(NPKM);4) high dose of NPK plus manure(1.5NPKM);and 5) NPK plus crop straw(NPKS). Over time, the grain yields of wheat and maize showed an increasing trend in all four fertilization treatments at the Yangling(YL) and Zhengzhou(ZZ) locations, while they declined at Qiyang(QY). The grain yield in the NPKM and 1.5NPKM treatments gradually exceeded that of the NPK and NPKS treatments at the QY site. The largest SYI was recorded in the NPKM treatment across the three sites, suggesting that inorganic fertilizer combined with manure can effectively improve crop yield sustainability. Higher SYI values were recorded at the YL and ZZ sites than at the QY site, possibly because the soil was more acid at QY. The key factors affecting grain yield were soil available phosphorus(AP) and available potassium(AK) at the YL and ZZ sites, and pH and AP at the QY site.All fertilization treatments resulted in soil N and P surpluses at the three sites, but soil K surpluses were recorded only at the QY site. The SFI was greater in the 1.5NPKM, NPKM and NPKS treatments than in the NPK treatment by 13.3–40.0 and 16.4–63.6% at the YL and ZZ sites, respectively, and was significantly higher in the NPKM and 1.5NPKM treatments than in the NPK and NPKS treatments at the QY site. A significant, positive linear relationship was found between SFI and crop yield, and SYI and nutrient balance, indicating that grain yield and its sustainability significantly increased with increasing soil fertility. The apparent N, P and K balances positively affected SFI.This study suggests that the appropriate amount of manure mixed with mineral NPK fertilizer is beneficial to the development of sustainable agriculture, which effectively increases the crop yield and yield sustainability by improving soil fertility. 展开更多
关键词 organic amendments crop yield yield sustainability soil fertility nutrient balance
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Fluid therapy in acute pancreatitis comparing balanced solutions and normal saline:A systematic review,meta-analysis and trial sequential analysis 被引量:1
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作者 Lin Gao Hsiang-Wei Wang +4 位作者 Zi-Rui Liu Yi-Zhen Xu Lu Ke Wei-Qin Li John A Windsor 《Hepatobiliary & Pancreatic Diseases International》 2025年第4期371-380,共10页
Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the t... Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the type of fluid are conflicting and generally come from small single-center randomized controlled trials(RCTs).We therefore conducted a systematic review and meta-analysis to compare the effect of balanced solutions(BS)versus NS on patient-centered clinical outcomes in AP.Methods:From four databases searched up to October 2024,we included only RCTs of adult patients with AP that compared the use of BS(including LR,acetate Ringer’s,etc.)with NS.The primary out-come was the disease advances from AP to moderately severe and severe AP(MSAP/SAP).Trial sequential analyses(TSA)were conducted to control for type-I and type-II errors and Grading of Recommendations Assessment,Development,and Evaluation(GRADE)was used to assess the quality of evidence.Results:Six RCTs were identified and included,involving 260 patients treated with BS and 298 patients with NS.Patients who received the BS had less MSAP/SAP[odds ratio(OR)=0.50,95%confidence in-terval(CI):0.29 to 0.85,P=0.01,I^(2)=0%;5 studies,299 patients],reduced the need of ICU admission(OR=0.60,95%CI:0.39 to 0.93,P=0.02,I^(2)=0%;5 studies,507 patients)and shorter length of hospital stay[mean difference(MD)=-0.88,95%CI:-1.48 to-0.28,P=0.004,I^(2)=0%;6 studies,558 patients;confirmed by TSA with high certainty]compared with those who received NS.The evidence for most of the clinical outcomes was rated as moderate to low due to the risk of bias,imprecision and inconsistency.Conclusions:BS,compared with NS,was associated with improved clinical outcomes in patients with AP.However,given the moderate to low quality of evidence for most of the outcomes assessed,further trials are warranted. 展开更多
关键词 Acute pancreatitis Fluid therapy Normal saline Balanced solution Systematic review
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China Can Achieve Carbon Neutrality in Line with the Paris Agreement's 2℃Target:Navigating Global Emissions Scenarios,Warming Levels,and Extreme Event Projections 被引量:1
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作者 Xiaoye Zhang Junting Zhong +4 位作者 Xiliang Zhang Da Zhang Changhong Miao Deying Wang Lifeng Guo 《Engineering》 2025年第1期207-214,共8页
This paper proposes that China,under the challenge of balancing its development and security,can aim for the Paris Agreement's goal to limit global warming to no more than 2℃by actively seeking carbonpeak and car... This paper proposes that China,under the challenge of balancing its development and security,can aim for the Paris Agreement's goal to limit global warming to no more than 2℃by actively seeking carbonpeak and carbon-neutrality pathways that align with China's national conditions,rather than following the idealized path toward the 1.5℃target by initially relying on extensive negative-emission technologies such as direct air carbon capture and storage(DACCS).This work suggests that pursuing a 1.5℃target is increasingly less feasible for China,as it would potentially incur 3–4 times the cost of pursuing the 2℃target.With China being likely to achieve a peak in its emissions around 2028,at about 12.8 billion tonnes of anthropogenic carbon dioxide(CO_(2)),and become carbon neutral,projected global warming levels may be less severe after the 2050s than previously estimated.This could reduce the risk potential of climate tipping points and extreme events,especially considering that the other two major carbon emitters in the world(Europe and North America)have already passed their carbon peaks.While natural carbon sinks will contribute to China's carbon neutrality efforts,they are not expected to be decisive in the transition stages.This research also addresses the growing focus on climate overshoot,tipping points,extreme events,loss and damage,and methane reductions in international climate cooperation,emphasizing the need to balance these issues with China's development,security,and fairness considerations.China's pursuit of carbon neutrality will have significant implications for global emissions scenarios,warming levels,and extreme event projections,as well as for climate change hotspots of international concern,such as climate tipping points,the climate crisis,and the notion that the world has moved from a warming to a boiling era.Possible research recommendations for global emissions scenarios based on China's 2℃target pathway are also summarized. 展开更多
关键词 Climate change 2℃target Carbon neutrality Emission scenarios Balanced mitigation
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Gut microbial characteristics of the damp-heat constitution:a population-based multicenter cross-sectional study 被引量:1
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作者 LI Tianxing ZHU Linghui +9 位作者 WANG Xueke TANG Jun YANG Lingling PANG Guoming LI Huang WANG Liying DONG Yang ZHAO Shipeng LI Yingshuai LI Lingru 《Journal of Traditional Chinese Medicine》 2025年第1期140-151,共12页
OBJECTIVE:To investigate the difference in gut microbiota between population with damp-heat constitution(DHC)and balanced constitution(BC).METHODS:A multi-centered cross-sectional casecontrol study was conducted,which... OBJECTIVE:To investigate the difference in gut microbiota between population with damp-heat constitution(DHC)and balanced constitution(BC).METHODS:A multi-centered cross-sectional casecontrol study was conducted,which included 249 participants with damp-heat constitution or balanced constitution.Baseline information of participants was collected,and stool samples were collected for gut microbiota analysis.Principal coordinate analysis,linear discriminant analysis effect size analysis,receiver operating characteristic,random forest model,and phylogenetic investigation of communities by reconstruction of unobserved states methods were used to reveal the relationship between gut microbiota and the damp-heat constitution.RESULTS:Compared to those in the BC group,the richness and diversity of the microbiota,specifically those of several short-chain fatty acid producing genera such as Barnesiella,Coprobacter,and Butyricimonas,were significantly decreased in the DHC group.Regarding biological functions,flavonoid biosynthesis,propanoate metabolism,and nucleotide sugar metabolism were suppressed,while arachidonic acid metabolism and glutathione metabolism were enriched in the DHC group.Finally,a classifier based on the microbiota was constructed to discriminate between the DHC and BC populations.CONCLUSION:The gut microbiota of the DHC population exhibits significantly reduced diversity and is closely related to inflammation,metabolic disorders,and liver steatosis,which is consistent with clinical observations,thus serving as a potential diagnostic tool for traditional Chinese medicine constitution discrimination. 展开更多
关键词 damp-heat constitution balanced constitution Traditional Chinese medicine constitution MICROBIOTA inflammatory PICRUSt multicenter study cross-sectional studies
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A novel carrier interleaved PWM method for four-level nested neutralpoint-clamped inverters 被引量:1
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作者 Wei Zhou Jupeng Pang +3 位作者 Mingzhe Wu Chao Wang Kui Wang Yongdong Li 《iEnergy》 2025年第1期65-76,共12页
The four-level nested neutral-point-clamped(4L-NNPC)inverter is a competitive topology among the various medium-voltage multilevel converters,and its main issue is flying-capacitor voltage unbalance.In this article,a ... The four-level nested neutral-point-clamped(4L-NNPC)inverter is a competitive topology among the various medium-voltage multilevel converters,and its main issue is flying-capacitor voltage unbalance.In this article,a novel carrier-interleaved pulse width modulation(CIPWM)method that satisfies the volt-sec balance principle is proposed with an advanced carrier distribution rule.By adopting the proposed CIPWM method,the redundant switching states of 4L-NNPC inverters can be evenly distributed into the output PWM waveform in each carrier period,and natural flying-capacitor voltage balance can be achieved.Furthermore,an active balancing strategy is also proposed to eliminate the voltage unbalance caused by nonideal factors,which is realized by simply adjusting the duty cycle and with no need to adjust the redundant switching states for 4L-NNPC inverters.The simulation and experimental results verify the effectiveness of the proposed CIPWM method and the flying-capacitor voltage balancing strategy. 展开更多
关键词 Multilevel converters capacitor voltage balance pulse width modulation
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Effect of inonotus obliquus polysaccharide on chronic nonbacterial prostatitis and its effect on Th17/Treg immune imbalance 被引量:1
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作者 Xiaoru Zhao Lihua Han +3 位作者 Miao Hao Lili Peng Hongxia Yuan Qingshan Li 《Journal of Chinese Pharmaceutical Sciences》 2025年第2期126-134,共9页
The aim of this study is to observe the therapeutic effect of Inonotus Obliquus Polysaccharide(IOP)on chronic nonbacterial prostatitis(CNP)and its effect on the helper T cells(Th17)and regulatory T cells(Treg)immune i... The aim of this study is to observe the therapeutic effect of Inonotus Obliquus Polysaccharide(IOP)on chronic nonbacterial prostatitis(CNP)and its effect on the helper T cells(Th17)and regulatory T cells(Treg)immune imbalance.The CNP rat models established by injecting Xiaozhiling injection were randomly divided into the model group,cernilton(40 mg/kg,i.g.)group and low-dose(35 mg/kg,i.g.),medium-dose(70 mg/kg,i.g.)and high-dose(140 mg/kg,i.g.)groups,with the same volume of saline injected into the same site as the control group.The prostate’s wet weight and body mass served as the basis for calculating the prostate index.The serum level of prostate-specific antigen(PSA)was detected by ELISA and the histopathology of prostate tissue was detected by HE staining.The protein expression of Foxp3,ROR-γt and STAT3 in rat prostatic tissue was determined by Western blot.The levels of Th17 and Treg cells infiltrated into the spleen were measured by flow cytometry.The results showed that treatment with IOP significantly reduced the levels of prostate index and serum PSA,and attenuated the pathological injury of the prostate tissue induced by CNP.With respect to samples induced by CNP alone,IOP treatment repressed the increased mRNA levels of IL-6,IL-17,IL-21,IL-23,ROR-γt and STAT3 in prostate tissue,while increasing the mRNA levels of IL-10,TGF-βand Foxp3 in prostate tissue.Meanwhile,IOP treatment attenuated the upregulation of the protein expression levels of ROR-γt and STAT3 in prostate tissue.Additionally,the protein expression of Foxp3 in prostate tissue was increased in the IOP-treated group.Flow cytometry analysis further demonstrated that IOP treatment regulated the balance between Th17 and Treg cells in the spleen in rat with CNP.Our study is the first to elucidate that IOP has significant therapeutic effects on CNP through regulation of Th17/Treg balance.Collectively,the study provides evidence for the potential of IOP to treat CNP. 展开更多
关键词 Inonotus obliquus polysaccharide Chronic nonbacterial prostatitis TH17 TREG Th17/Treg balance
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Berg Balance Scale score is a valuable predictor of all-cause mortality among acute decompensated heart failure patients 被引量:1
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作者 Yu-Xuan FAN Jing-Jing CHENG +7 位作者 Zhi-Qing FAN Jing-Jin LIU Wen-Juan XIU Meng-Yi ZHAN Lin LUO Guang-He LI Le-Min WANG Yu-Qin SHEN 《Journal of Geriatric Cardiology》 2025年第6期555-562,共8页
OBJECTIVE To investigate possible associations between physical function assessment scales,such as Short Physical Performance Battery(SPPB)and Berg Balance Scale(BBS),with all-cause mortality in acute decompensated he... OBJECTIVE To investigate possible associations between physical function assessment scales,such as Short Physical Performance Battery(SPPB)and Berg Balance Scale(BBS),with all-cause mortality in acute decompensated heart failure(ADHF)patients.METHODS A total of 108 ADHF patients were analyzed from October 2020 to October 2022,and followed up to May 2023.The association between baseline clinical characteristics and all-cause mortality was analyzed by univariate Cox regression analysis,while for SPPB and BBS,univariate Cox regression analysis was followed by receiver operating characteristic curves,in which the area under the curve represented their predictive accuracy for all-cause mortality.Incremental predictive values for both physical function assessments were measured by calculating net reclassification index and integrated discrimination improvement scores.Optimal cutoff value for BBS was then identified using restricted cubic spline plots,and survival differences below and above that cut-off were compared using Kaplan-Meier survival curves and the log-rank test.The clinical utility of BBS was measured using decision curve analysis.RESULTS For baseline characteristics,age,female,blood urea nitrogen,as well as statins,angiotensin-converting enzyme inhibitors,angiotensin II receptor blockers,or angiotensin receptor-neprilysin inhibitors,were predictive for all-cause mortality for ADHF patients.With respect to SPPB and BBS,higher scores were associated with lower all-cause mortality rates for both assessments;similar area under the curves were measured for both(0.774 for SPPB and 0.776 for BBS).Furthermore,BBS≤36.5 was associated with significantly higher mortality,which was still applicable even adjusting for confounding factors;BBS was also found to have great clinical utility under decision curve analysis.CONCLUSIONS BBS or SPPB could be used as tools to assess physical function in ageing ADHF patients,as well as prognosticate on all-cause mortality.Moreover,prioritizing the improvement of balance capabilities of ADHF patients in cardiac rehabilitation regimens could aid in lowering mortality risk. 展开更多
关键词 physical function assessment scalessuch Acute Decompensated Heart Failure All Cause Mortality Physical Function Assessment berg balance scale bbs short physical performance battery sppb univariate cox regression analysiswhile Short Physical Performance Battery
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Effect of Direct Current on Wetting of Cu Substrate in Liquid Sn Solder
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作者 Sun Xuemin Zhu Weiwei +1 位作者 Yu Weiyuan Wu Baolei 《稀有金属材料与工程》 北大核心 2025年第6期1445-1450,共6页
The wetting behavior of liquid tin(Sn)solder on copper(Cu)substrate at 250℃was investigated by the wetting balance method under the action of direct current(DC).The curves of wetting balance were measured and the mor... The wetting behavior of liquid tin(Sn)solder on copper(Cu)substrate at 250℃was investigated by the wetting balance method under the action of direct current(DC).The curves of wetting balance were measured and the morphology of the intermetallic compound(IMC)precipitated at the interface were observed.Results show that DC has a significant effect on the wettability and IMC.As the current increases,the balance wetting force and the thickness of the IMC layer increase.The direction of the DC also has a certain effect on the balance wetting force and IMC layer.When the current is negative,the final balance wetting force and the thickness of the Cu_(6)Sn_(5) layer are significantly higher than those in the positive current case,which is attributed to electromigration.The IMC precipitation at the interface provides a chemical driving force for the movement of the triple junction.The interaction of the interface atoms and the chemical reaction are enhanced by DC,thereby improving wettability.Meanwhile,the Marangoni convection caused by DC inside liquid Sn solder changes the structure of triple junction,which provides a physical driving force for the spread of the liquid Sn solder on the Cu substrate. 展开更多
关键词 wetting balance method DC interfacial reaction IMC Marangoni convection
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Performance analysis of scramjet including magnetohydrodynamic power generation after combustor
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作者 LIU Chenyuan WU Shaoxun MENG Hao 《推进技术》 北大核心 2025年第8期15-28,共14页
To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a b... To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a benchmark scramjet performance evaluation model.Based on the test data of typical flying point of Mach 7 with the altitude of 29 km,the reliability of the model was verified.The deviations of parameters such as the to⁃tal pressure loss of combustor between the model and the test data were analyzed.Furtherly,an analytical method for post-combustion magnetohydrodynamic power generation was established;by embedding the above method into the overall performance evaluation model,performance prediction considering the power generation effect was realized.Finally,based on the above model,variety regulations of the inlet and the outlet parameters of the power generation channel and performance parameters including the engine specific impulse and the unit thrust under different enthalpy extraction ratios and load factors were analyzed.It could be concluded that the model can reliably predict the variations of key parameters.As the value of the load factor increases,the value of the conduc⁃tivity required to reach the specified enthalpy extraction ratio first decreases and then increases,which is approxi⁃mately parabolic.In order to reduce the demand for the gas conductivity for MHD power generation,the load fac⁃tor should be around 0.5.When the load factor is 0.4 and the magnetic induction intensity is 2.5 T,if the enthalpy extraction ratio reaches 0.5%,the engine specific impulse performance reduces about 3.58%. 展开更多
关键词 SCRAMJET Energy bypass Magnetohydrodynamic power generation Chemical balance Performance evaluation
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Dual encoding feature filtering generalized attention UNET for retinal vessel segmentation
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作者 ISLAM Md Tauhidul WU Da-Wen +6 位作者 TANG Qing-Qing ZHAO Kai-Yang YIN Teng LI Yan-Fei SHANG Wen-Yi LIU Jing-Yu ZHANG Hai-Xian 《四川大学学报(自然科学版)》 北大核心 2025年第1期79-95,共17页
Retinal blood vessel segmentation is crucial for diagnosing ocular and cardiovascular diseases.Although the introduction of U-Net in 2015 by Olaf Ronneberger significantly advanced this field,yet issues like limited t... Retinal blood vessel segmentation is crucial for diagnosing ocular and cardiovascular diseases.Although the introduction of U-Net in 2015 by Olaf Ronneberger significantly advanced this field,yet issues like limited training data,imbalance data distribution,and inadequate feature extraction persist,hindering both the segmentation performance and optimal model generalization.Addressing these critical issues,the DEFFA-Unet is proposed featuring an additional encoder to process domain-invariant pre-processed inputs,thereby improving both richer feature encoding and enhanced model generalization.A feature filtering fusion module is developed to ensure the precise feature filtering and robust hybrid feature fusion.In response to the task-specific need for higher precision where false positives are very costly,traditional skip connections are replaced with the attention-guided feature reconstructing fusion module.Additionally,innovative data augmentation and balancing methods are proposed to counter data scarcity and distribution imbalance,further boosting the robustness and generalization of the model.With a comprehensive suite of evaluation metrics,extensive validations on four benchmark datasets(DRIVE,CHASEDB1,STARE,and HRF)and an SLO dataset(IOSTAR),demonstrate the proposed method’s superiority over both baseline and state-of-the-art models.Particularly the proposed method significantly outperforms the compared methods in cross-validation model generalization. 展开更多
关键词 Vessel segmentation Data balancing Data augmentation Dual encoder Attention Mechanism Model generalization
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